Old Prussians in the context of "Western Balts"

The Kingdom of Lithuania was a sovereign state that existed from 17 July 1251 until the death of the first crowned king of Lithuania, Mindaugas, on 12 September 1263. Mindaugas was the only Lithuanian monarch crowned king with the assent of the Pope and the head of the first Catholic Lithuanian state. The formation of the kingdom is widely regarded as a partially successful attempt at unifying all surrounding Baltic tribes, including the Old Prussians, into a single unified state under a common king.

Other monarchs of Lithuania were referred to as grand dukes, kings or emperors in extant foreign written sources as the size of the realm and their power expanded or contracted. This practice can be compared to that of British, Japanese and many other monarchs who are known as kings or emperors in spite of not being crowned with the assent of the Pope. Because Lithuania was pagan in the 13th century, Lithuanian monarchs were not granted the title of a Catholic monarch, even though extant Christian sources referred to Lithuanian rulers as kings or emperors regardless of their religious affiliation. For instance, Gediminas titled himself King of Lithuania and Rus, and Duke of Semigalia. The Pope also addressed him as King.

Lithuanian mythology (Lithuanian: Lietuvių mitologija) is the mythology of Lithuanian polytheism, the religion of pre-Christian Lithuanians. Like other Indo-Europeans, ancient Lithuanians maintained a polytheistic mythology and religious structure. In pre-Christian Lithuania, mythology was a part of polytheistic religion; after Christianisation, mythology survived mostly in folklore, customs, and festive rituals. Lithuanian mythology is very close to the mythology of other Baltic nations, such as Prussians and Latvians, and is considered a part of Baltic mythology.

The Balts or Baltic peoples (Lithuanian: baltai, Latvian: balti) are a group of peoples inhabiting the eastern coast of the Baltic Sea who speak Baltic languages. Among the Baltic peoples are modern-day Lithuanians (including Samogitians) and Latvians (including Latgalians) — all East Balts — as well as the Old Prussians, Curonians, Sudovians, Skalvians, Yotvingians and Galindians — the Western Balts — whose languages and cultures are now extinct, but made a large influence on the living branches, especially on literary Lithuanian language.

The Balts are descended from a group of Proto-Indo-European tribes who settled the area between the lower Vistula and southeast shore of the Baltic Sea and upper Daugava and Dnieper rivers, and which over time became differentiated into West and East Balts. In the fifth century CE, parts of the eastern Baltic coast began to be settled by the ancestors of the Western Balts, whereas the East Balts lived in modern-day Belarus, Ukraine and Russia. In the first millennium CE, large migrations of the Balts occurred. By the 13th and 14th centuries, the East Balts shrank to the general area that the present-day Balts and Belarusians inhabit.

Königsberg is the historic German and Prussian name of the city now called Kaliningrad, Russia. The city was founded in 1255 on the site of the small Old Prussian settlement Twangste by the Teutonic Knights during the Baltic Crusades. It was named in honour of King Ottokar II of Bohemia, who led a campaign against the pagan Old Prussians, a Baltic tribe.

A Baltic port city, it successively became the capital of the State of the Teutonic Order, the Duchy of Prussia and the provinces of East Prussia and Prussia. Königsberg remained the coronation city of the Prussian monarchy from 1701 onwards, though the capital was Berlin. From the thirteenth to the twentieth centuries on, the inhabitants spoke predominantly German, although the city also had a profound influence upon the Lithuanian and Polish cultures. It was a publishing center of Lutheran literature; this included the first Polish translation of the New Testament, printed in the city in 1551, as well as the first book in Lithuanian and the first Lutheran catechism, both printed in Königsberg in 1547.

Prussia (/ˈprʌʃə/; German: Preußen [ˈpʁɔʏsn̩] ; Old Prussian: Prūsija) was a German state centred on the North European Plain that originated from the 1525 secularization act of the Prussian part of the State of the Teutonic Order. For centuries, the House of Hohenzollern ruled Prussia, expanding its size with the Prussian Army. Prussia, with its capital at Königsberg and then, when it became the Kingdom of Prussia in 1701, Berlin, decisively shaped the history of Germany. Prussia formed the German Empire when it united the German states in 1871. It was de facto dissolved by an emergency decree transferring powers of the Prussian government to German Chancellor Franz von Papen in 1932 and de jure by an Allied decree in 1947.

The name Prussia derives from the Old Prussians who were conquered by the Teutonic Knights – an organized Catholic medieval military order of German crusaders – in the 13th century. In 1308, the Teutonic Knights conquered the region of Pomerelia with Danzig. Their monastic state was mostly Germanised through immigration from central and western Germany, and, in the south, it was Polonised by settlers from Masovia. The imposed Second Peace of Thorn (1466) split Prussia into the western Royal Prussia, a province of Poland, and the eastern Duchy of Prussia, a feudal fief of the Crown of Poland until 1657. After 1525, the Teutonic Order relocated their headquarters to Mergentheim, but managed to keep land in Livonia until 1561. The union of Brandenburg and the Duchy of Prussia in 1618 led to the proclamation of the Kingdom of Prussia in 1701.

East Prussia (German: Ostpreußen [ˈɔstˌpʁɔɪ̯sn̩] ) was a province of the Kingdom of Prussia from 1772 to 1829 and again from 1878 (with the Kingdom itself being part of the German Empire from 1871); following World War I it formed part of the Weimar Republic's Free State of Prussia, until 1945. Its capital city was Königsberg (present-day Kaliningrad). East Prussia was the main part of the region of Prussia along the southeastern Baltic Coast.

The bulk of the ancestral lands of the Baltic Old Prussians were enclosed within the later province of East Prussia. During the 13th century, the native Prussians were conquered by the crusading Teutonic Knights. After the conquest they were gradually converted to Christianity. As a result of the medieval Ostsiedlung, Germans became the dominant ethnic group, while Poles and Lithuanians formed sizeable minorities. From the 13th century, the region of Prussia was part of the monastic state of the Teutonic Knights. After the Second Peace of Thorn in 1466 it became a part of the Kingdom of Poland, either directly (Warmia) or as a fief (remainder). In 1525, with the Prussian Homage, the territory became the Duchy of Prussia, a vassal duchy of Poland. It gained full sovereignty in 1657, when Poland renounced its feudal rights in the Treaty of Bromberg.

The Thirteen Years' War (Polish: wojna trzynastoletnia; German: Dreizehnjähriger Krieg), also called the War of the Cities, was a conflict fought in 1454–1466 between the Crown of the Kingdom of Poland and the Teutonic Order.

After the enormous defeat suffered by the German Order at the hand of Poland-Lithuania in 1410 and the ensuing political, military and economic problems, the state was rife with internal conflict between the ruling Order and the native Prussian warlords, who shared concerns with assimilated Prussian and German townsfolk. Eventually this tension led to an uprising by the Prussian Confederation representing the local Prussian nobility and cities, who sought the protection of the Polish King Casimir IV Jagiellon. This essentially amounted to a switching of sides which the German Order immediately took as a mortal threat, and a war broke out between Poland and the Teutons.

The Lithuanian Crusade was a series of campaigns by the Teutonic Order and the Livonian Order under the pretext of forcibly Christianizing the pagan Grand Duchy of Lithuania. The Livonian Order occupied Riga in 1202 and in the 1230s they settled in Chełmno Land, a fief of Poland. They first conquered other neighboring Baltic tribes— proto-Latvians (Curonians, Semigallians, Latgalians, Selonians) and Old Prussians—in the Livonian Crusade and Prussian Crusade.

The first raid against the Lithuanians and Samogitians was in 1208. From then on, the orders played a key role in Lithuanian politics, but they were not a direct threat until the 1280s. By that time, the Grand Duchy of Lithuania was already a centralized state and could mount defenses. For the next century, the order organized annual colonialist reise (raids) into Samogitian and Lithuanian lands, without great success but at immense human cost. Border regions in Samogitia and Suvalkija became sparsely inhabited wilderness due to ethnic cleansing, although the order gained very little territory. The resulting wars between the Teutonic Order and Lithuania were one of the longest conflicts in the history of Europe.